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Ser ut til at det holder med å bruker GROUP BY...

hvis du kun skal bruge én værdi for hver kendetegn, så er det DISTINCT du skal bruge...

Det her er taget fra: http://www.w3schools.com/sql/sql_select.asp (hjemmesiden er genial som introduktion til mange emner, så som SQL, HTML, XML, JavaScript mm.)

The SELECT DISTINCT Statement
The DISTINCT keyword is used to return only distinct (different) values.

The SELECT statement returns information from table columns. But what if we only want to select distinct elements?

With SQL, all we need to do is to add a DISTINCT keyword to the SELECT statement:

Syntax
SELECT DISTINCT column_name(s)
FROM table_name


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Using the DISTINCT keyword
To select ALL values from the column named "Company" we use a SELECT statement like this:

SELECT Company FROM Orders

"Orders" table

Company OrderNumber
Sega 3412
W3Schools 2312
Trio 4678
W3Schools 6798

Result

Company
Sega
W3Schools
Trio
W3Schools

Note that "W3Schools" is listed twice in the result-set.

To select only DIFFERENT values from the column named "Company" we use a SELECT DISTINCT statement like this:

SELECT DISTINCT Company FROM Orders

Result:

Company
Sega
W3Schools
Trio

Now "W3Schools" is listed only once in the result-set.

Nice!!!!

Takk for tipset om w3school.com

velbekomme, bruger den MEGET hvis jeg støder på noget nyt, eller hvis jeg har glemt hvordan man gør.

Dem der har lavet den hjemmeside burde have en premie for indsatsen